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11.
还是在液晶显示器最初普及的阶段,省略了DVI接口的产品曾经是霸占整个低端液晶市场的绝对主流。不过到了2007年,液晶显示器的发展开始快速变化,具备DVI+VGA接口的液晶显示器已经成为了市场主流。而正是在这个时候,市场上还存留着一批省略了DVI接口的低价液晶。在这样的市场环境下,省略DVI的低价液晶到底值不值得购买?也就成为了人们争论的焦点。[编者按]  相似文献   
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HYDRUS-1D was used to simulate water flow and leaching of fecal coliforms and bromide (Br) through six undisturbed soil lysimeters (70 cm depth by 50 cm diameter) under field conditions. Dairy shed effluent (DSE) spiked with Br was applied to the lysimeters, which contained fine sandy loam layers. This application was followed by fortnightly spray or flood water irrigation. Soil water contents were measured at four soil depths over 171 days, and leachate was collected from the bottom. The post-DSE period simulations yielded a generally decreased saturated water content compared to the pre-DSE period, and an increased saturated hydraulic conductivity and air-entry index, suggesting that changes in soil hydraulic properties (e.g. via changes in structure) can be induced by irrigation and seasonal effects. The single-porosity flow model was successful in simulating water flow under natural climatic conditions and spray irrigation. However, for lysimeters under flood irrigation, when the effect of preferential flow paths becomes more significant, the good agreement between predicted and observed water contents could only be achieved by using a dual-porosity flow model. Results derived from a mobile-immobile transport model suggest that compared to Br, bacteria were transported through a narrower pore-network with less mass exchange between mobile and immobile water zones. Our study suggests that soils with higher topsoil clay content and soils under flood irrigation are at a high risk of bacteria leaching through preferential flow paths. Irrigation management strategies must minimize the effect of preferential flow to reduce bacterial leaching from land applications of effluent.  相似文献   
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This study examined the psychometric properties of the Readiness and Motivation Interview (RMI), a symptom-specific measure of readiness and motivation for change in the eating disorders. For 4 symptom domains, the RMI assesses the extent to which individuals are in precontemplation, contemplation, and action/maintenance, and the extent to which change is made for internal versus external reasons. Ninety-nine individuals with eating disorders completed the RMI and measures to assess convergent, divergent, and criterion validity. RMI profiles revealed differences in readiness and motivation across symptom domains. The RMI demonstrated good reliability and construct validity, and RMI scores predicted anticipated difficulty of recovery activities, completion of recovery activities, decision to enroll in an intensive symptom-reduction program, and treatment dropout. The RMI may have important clinical applications by providing much-needed information on client readiness for action-oriented treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
14.
Residential eating disorder treatment involves emotional, financial, and time commitments from clients, staff, and the health care system. At discharge, most clients have made substantial nutritional, social, and psychological changes. However, maintaining these changes when intensive support is no longer available represents a significant challenge, and it is common for individuals to slip back into previous eating disorder patterns. Interviews with 32 individuals were conducted 6 months after discharge. Qualitative analyses revealed a pattern of factors that facilitated and hindered recovery. These factors were integrated with past research findings to develop a conceptual model about how changes are maintained. Recommendations regarding ways that health care professionals can assist with the transition from intensive treatment to community living are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The present work mainly deals with the testing and modeling of a commercially-available copper indium diselenide (CIS) ST40 module from the former Siemens Solar Industries (SSI). For this purpose, a large quantity of current/voltage characteristics were measured in the Paul Scherrer Institute (PSI)’s photovoltaic test-facility under different cell temperatures, solar irradiation and air mass, AM, conditions. They were used to develop a semi-empirical efficiency model to correlate all measured data sets. The goal was to make available a model, allowing quick and accurate calculation of the performance of the CIS module under all relevant operating conditions.

For the undegraded state of the module, the efficiency model allowed us to deduce the efficiency at Standard Test Conditions, STC, and its temperature coefficient at STC, which were 11.58% and minus 0.050%/°C, respectively. The output of the undegraded module under STC was found to be 42.4 W, i.e., 6% higher than specified by the manufacturer (40 W). Furthermore, the efficiency does not decrease with increasing air mass. At a cell temperature of 25 °C and a relative air mass of 1.5, the module has a maximum in efficiency of 12.0% at an irradiance of about 650 W/m2. This indicates that the series-resistance losses become significant at higher irradiances. Hence, improving the transparent conducting oxide (TCO) electrode on the front side of the cells might lead to a higher output at high irradiances.

Identical testing and modeling were repeated after having exposed the module to real weather conditions for one year. We found that the STC efficiency was reduced by 9.0%, from 11.58 down to 10.54%. The temperature coefficient of the efficiency had changed from minus 0.050 %/°C to minus 0.039%/°C. These results indicate possible chemical changes in the semiconductor film. The output of the module at STC was reduced by 9.0% from 42.4 W down to 38.6 W.

Using meteorological data from a sunny site in the South of Jordan (Al Qauwairah) and the efficiency model presented here allows us to predict the yearly electricity yield of the CIS module in that area. Prior to degradation, the yield was found to be 362 kWh/m2 for the Sun-tracked module; and 265 kWh/m2 for the fix-installed module (South-oriented, at an inclination angle of 30°). After degradation the corresponding yields were found to be 334 and 241 kWh/m2; meaning losses of 8.4% and 9.5%, respectively. (Note: all units of energy, kWh, are referred to the active cell area.) Having available efficiency models for other module types, similar predictions of the yield can be made, facilitating the comparisons of the yearly yields of different module types at the same site. This in turn allows selecting the best module type for a particular site.  相似文献   

17.
The consensus of the '92 Rio summit was that all development should aim for non-depletion of the earth's resources.The major growth region for the next decade is SE Asia and particularly the cities of South China for which Hong Kong is a role model with its dense urban construction. Recent Hong Kong energy legislation addressed the thermal transmission of the envelope without integrating building services energy consumption while planning legislation determines plot ratio but does not restrict overall building height in most areas of Hong Kong. A recently constructed high-rise commercial building has been analysed and proposed modifications computer modelled to evaluate options to extend daylight deeper into the space using extra interior height, alternative glazing and an external lightshelf. The commercial programme Lightscape, recently developed, is being assessed as a design tool to visually simulate the interior lighting, the illumination levels and daylight factors verified against scale physical models.  相似文献   
18.
Energy storage is an important feature of many solar energy systems. Because of the small temperature potentials available from flat plate collectors, large masses and volumes are involved when energy is stored by raising or lowering the temperature of a tank of fluid or bed of gravel. This paper proposes energy storage in the form of heat of adsorption in beds of adsorbent material. This is most readily achieved by nominating water as the adsorbate so that water vapour is transferred to or from the absorbent from the humid air flowing through the bed. The large heat of adsorption means that the adsorption of a small mass of water liberates a large amount of energy which mostly is transferred to the air stream. It is shown that adsorbing materials can occupy a much smaller volume than non-adsorbing materials for the same quantity of energy stored, and that thermal insulation can be dispensed with. Provided that the container is impervious to water vapour, energy can be stored indefinitely.  相似文献   
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We have the opportunity to evaluate a portable ambulatory device for the recording of sequential indirect arterial blood pressure and continuous electrocardiogram (Del Mar Avionics automatic ambulatory blood pressure recording device). With careful attention to technique, only 11% of systolic and 5% of diastolic blood pressure readings differed by more than 10 mm Hg as compared with a trained technician's observations simultaneously in the same arm. The device has been useful in the evaluation of borderline (labile) hypertension, hypertensive drug therapy programs, and various episodic cardiovascular phenomena--for example, vasodepressor syncope and pheochromocytoma crises.  相似文献   
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